Fix bug in snap points parsing logic
Fix bug in snap points parsing logic

The wrong variable was being checked for positive value
in the original CL: https://codereview.chromium.org/1188643005

This fixed the build failure after r198211.

BUG=311234
TBR=timloh,mvanouwerkerk

Review URL: https://codereview.chromium.org/1222213002

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@198232 bbb929c8-8fbe-4397-9dbb-9b2b20218538

Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk,Pluto-tv/blink-crosswalk